After college, it takes four years to complete medical school and three years to complete a general pediatrics residency. See if you can volunteer in a pediatricians office to see what it is like. You will get good experience and maybe some advice that is helpful. It will help you know if it is like what you are thinking and can help you feel even more certain about your goals. You could also see if you could sit down with a pediatrician and find out why they went into medicine and pediatrics. See what they like about their job and what they don't like. Good luck!
It takes 10 years to train such an experienced pediatrician at least.